Technical Field
The disclosure relates to a light emitting device, more particularly to a light emitting device emitting light via one or more light emitting diodes.
Related Art
Light emitting diodes (LED) are characterized by having a relatively-long lifespan, a relatively-small size, a relatively-good earthquake-resistant ability, relatively-low thermal production and relatively-low power consumption, so recently they have been used as indicators or light sources in a variety of equipment. Moreover, multicolor and high-brightness light emitting diodes are being developed and applied to larger outdoor billboards, traffic lights and relevant fields. In the future, it is very possible to use light emitting diodes as the main illumination light sources with power saving and environmental protection functions.
However, as a conventional light emitting device using a light emitting diode string to provide a light source, light emitting diodes in the light emitting diode string were typically turned on in a specific order, so components respectively corresponding to the light emitting diodes needed to bear a relatively-high voltage difference between their two ends. Therefore, these components in such a conventional light emitting device usually have high voltage-endurance. Also, since a high voltage-endurance component requires a relatively-low working current, the light emitting device would need more or larger high voltage-endurance components. This manner brought in the limitation in the circuit design and led to a higher manufacturing cost of the light emitting device.